Study On Structural Development Characteristics Of Central Mining Area In Qianyingzi Coal Mine And Its Influence On Mining Geological Conditions

The first and second mining area in the western part of the mine and the first mining area in the eastern part in Qianyingzi coal mine in northern Anhui have been completed.In order to meet the demand of mine production replacement,the layout and mining of the working face in the middle mining area need to be carried out urgently.At present,the exploration degree in the middle mining area of the mine is low,and there is no production exposure.In order to ensure the safe and efficient development and mining of the mining area,it is necessary to study the structural development characteristics of the middle mining area and its influence on the mining geological conditions.Taking Qianyingzi Coal Mine as the research object,and on the basis of systematically collecting and sorting out the relevant data of mine exploration and mining in the past.The development characteristics and formation mechanism of mine regional structure were analyzed by using the methods of structural geology principle analysis,exploration and mining comparison,projection pursuit,etc.,Based on this,the development characteristics and formation and evolution law of central mining area were studied,and the complexity of geological structure in central mining area was evaluated.Combined with the comparison results of exploration and mining,the structural development in the central mining area is further analyzed,and the influence of geological structure on coal seam and gas occurrence and surrounding rock stability in the central mining area is discussed.The research results provide a basis for the subsequent development and mining in the central mining area of the mine.The main achievements are as follows:（1）The main structural styles in each fault block of the mine include:extensional structural combination,compressive structural combination and strike-slip structural type.Based on the analysis of regional tectonic evolution law,the formation mechanism of large folds and faults in the mine,such as Fengjia syncline,DF₂₀₀,F₁₅ fault and F₁₇ fault,and associated small structures are systematically matched by stages,and the structural deformation of coal measures strata in the mine is divided into five stages.（2）The overall structural form of the mining area in the middle of the mine is a syncline structure（Fengjia syncline）distributed in the axial NNE direction.The scale and quantity of reverse faults in the area control the overall structural framework in the mining area.The nature and geometric characteristics of faults in the mining area are basically consistent with the statistical results of geological data of the whole mine,and the fault structure can be divided into four periods.（3）Based on the structural development characteristics of the central mining area,several indexes,such as fracture fractal dimension,are selected,and the optimal projection direction of each evaluation index is determined by the projection pursuit method.An Arc GIS comprehensive evaluation model is established,and the structural complexity of the central mining area is divided into four grades,namely,the structurally complex area,the structurally complex area,the structurally medium area and the structurally simple area,and the areas with relatively complex geological structures are mainly distributed in NNE-to-F₁₇fault and F_17-2 fault and their two sides,revealing that.（4）Based on the geological data of mine exploration and actual mining,the comparative study of structural exploration and mining is carried out.The results show that there are great changes in the occurrence,elements and quantity of faults between the geological exploration data of mine and the exposed data of actual production,and the development characteristics of faults after actual exposure are more complicated than those of exploration data.（5）The weights of main control factors affecting the complexity of coal seam structure in central mining area are determined by AHP method,and the complexity of coal seam is evaluated.The results show that the complexity of coal seam geological structure in 3₂ coal seam in central mining area is unstable and complex.The distribution law of gas content is influenced by small structures,and the gas content in the developed parts of the central mining area is high.This paper expounds the control function of geological structures on the mining geological conditions,and puts forward the mining countermeasures in the central mining area.The research results have certain guiding significance for the next study on the mining geological conditions in the central mining area and the prevention and control of mine geological disasters.Figure[65]Table[25]Reference[87]...